Blends of polyvinyl chloride with homopolymers and copolymers of alkyl beta-vinylpropionate



United States Patent Delaware No Drawing. Filed June 22, 1962, Ser. No. 204,602

8 Claims. (Cl. 260897) This invention relates to homopolymers and copolymers of alkyl B-vinylpropionates, methods of preparing such polymers and copolymers, and blends thereof with polyvinyl chloride and copolymers of vinyl chloride in preponderance with other monomers.

Alkyl B-vinylpropionates are known compounds. See, for example, E. J. Boorman et al., J.C.S., 568 (1933).

It has now been found that homopolymers of alkyl ,B-vinylpropionates and copolymers thereof with other monomers, such as ethylene, ethyl acrylate, diethyl fumarate and diethyl maleate, possess a unique combination of properties that make them particularly suitable for use as plasticizers for polyvinyl chloride and copolymers containing a preponderance of vinyl chloride. In particular, good flexibility without sacrifice of other desirabl properties is imparted to polyvinyl chloride when said polymers and/ or copolymers are blended therewith. Furthermore, such blends are unique in that they possess exceptional permanence as evidenced by their low volatility and hexane extraction values coupled with good volume resistivity.

The alkyl fi-vinylpropionates of particular interest are those in which the .alkyl group contains one to four carbon atoms. These compounds can be polymerized or copolymerized with other monomers having polymerizable ethylenic unsaturation, such as ethylene, ethyl acrylate, diethyl fumarate and diethyl maleate in amounts up to about 75%, with free radical initiators. Such initiators are used at levels of from about 0.1 to about 15 mole percent. The preferred range is 3 to 10 mole percent. Common free radical initiators may be used, for example t-butyl peracetate, di-t-butyl peroxide, diisobutylene ozonide, and other olefin ozonides.

The polymers and copolymers of particular concern are those having a molecular weight within the range of about 500 to about 2500, and preferably 1000 to 1500.

The following examples illustrate the preparation of typical polymers and copolymers within the scope of this invention.

Example 1.Hmopolymerizati0n of ethyl S-vinylpropionate using t-butyl peracetate as catalyst Ethyl fl-vinylpropionate, 256 g., and t-butyl peracetate, 17.60 g., were charged to a stirred reactor equipped for reflux and heated to 115 C. The temperature was then slowly raised to 135 C. over a 5 hour period. The prodnot was stripped of volatile materials to a temperature of 190 C. at 0.15 mm. of Hg pressure. There remained as a pot residue 112.3 g. of the homopolymer of ethyl ,B-vinylpropionate, which had a molecular weight of 929117 and a Gardner Holdt viscosity of T.

Example 2. Homopolymerization of ethyl B-vinylpropionate using diisobutylene ozonide as a catalyst Using 218 g. of ethyl S-vinylpropionate and 27.3 g. of diisobutylene ozonide added as an 18.1% solution in Skelly Solvent C, an 85.4 g. yield of the homopolymer of ethyl B-vinylpropionate was obtained, having amolecular weight of 672 and a Gardner Holdt viscosity of N+.

3,264,377 Patented August 2, 1966 Example 3.'C0p'olymerizati0n of ethyl fl-vinylpropionate and ethyl acrylate Ethyl fl-vinylpropionate, 230.4 g., ethyl acrylate, 25.6 g., and t-butyl peracetate, 17.6 g., were charged to a stirred reactor equipped for reflux and heated to C. The temperaturewas then slowly raised to 137 C. over a 2.5 hour period. The product was stripped to a temperature of 202 C. at a pressure of 0.15 mm. of Hg. There remained as a pot residue 158.0 g. of a copolymer of ethyl fi-vinylpropionate and ethyl acrylate, having a molecular weight of 1530150 and a Gardner Holdt viscosity of Z Example 4.C0p0lymerizati0n of ethylene and ethyl fi-vinylpropionate Ethylene, 84 g., was introduced to a chilled (40 C.) reservoir from a cylinder of known volume. Ethyl fl-vinylpropionate, 384 g., hexane, 192 g., and 97% di-t-butyl peroxide, 45.2 g., were added to the reservoir and the reactants were mixed with ethylene by stirring. The reservoir contents were pressurized to 500 p.s.i. with nitrogen, and the entire reaction mixture was metered by means of a high pressure proportioning pump into a coil reactor of 8 ml. volume. The latter was immersed in a constant temperature bath held at 250 C. The reaction pressure in the hot coil was 5000 p.s.i. and was maintained by a high pressure let-down valve and control system. The rate of feed of reactants was so adjusted that the eflluent from the hot coil was ollected (via the let-down valve) at about 4 g. per minute; gaseous eflluent was permitted to escape to the atmosphere. The total running time was 131 minutes and a total of 579.3 g. of liquid products was obtained. Forerun and afterrun, totaling 131.2 g., were discarded and a center cut of 448.1 g. stripped to a flask temperature of 200 C. at a vacuum of less than 1 mm. of Hg. There was obtained 128.3 g. of a copolymer of ethyl fl-vinylpropionate and ethylene with a molecular weight of 744 :and a Gardner Holdt viscosity of E. The ratio of ethylene to ethyl fi-vinylpropionate was 1.06 as calculated from a carbon analysis of 69.42%.

The following table shows values found as a result 'of standard tests run on blends of a commercially available polyvinyl chloride (Ge'on 101) with the homopolymer of Example 1 and the copolymer of Example 3, when compared with blends in equal amounts of the same polyvinyl chloride with a commercially available polyester plasticizer (P-araplex G-50) and with a monomeric plasticizer (dioctyl phthalate).

2 Blends of PVC (60%) and Plasticizer (40%). 3 Blends of PVC (65%) and Plasticizer (35%).

From the above table it is evident that the polymers of present concern when blended with PVC show a high degree of permanence plus good electrical properties. It is evident, therefore, that they represent a substantial advance in the art.

What is claimed is:

1. A blend of (a) a member of the group consisting of polyvinyl chloride and copolymers of vinyl chloride with a minor amount of another monomer copolymerizable therewith and (b) a member of the group consisting of homo 3 polymers of an alkyl ,B-vinylpropionate in which. the alkyl group contains one to four carbon atoms and copolymers thereof with another monomer copolymerizable therewith.

2. A blend as in claim 1 wherein (b) is a homopolymer as therein defined.

3. A blend as in claim 1 wherein (b) is a copolyrmer as therein defined. -v 4. A blend as in claim 1 wherein (b) is a homopolyrner of methyl fi-vinylpropionate.

5. A blend as in claim 1 wherein of ethyl B-vinylpropionate. 6.:A 'blendas in claim lwherein (b) is a copolymer (b) is a homopolymer of an :alkyl ,fi-vinylpropionate having one to four carbon atoms in the alkyl group and ethyl acr yl-ate.

7. A 'blend as in claim 1 wherein (b) is a'copolymer atoms in the alkyl group and ethylene.

A blend as in claim 1 wherein (b) "isa copolymer.

of an alkyl fl-vinylpropionate having one to four carb UNITED STATES PATENTS 7/1949 Adelsonetal. 260*897 E. I. Boomaniet aL: Journal of Chemical Society, 568

1b (193 3'), copy in ScientificiLibrary;

7 OTHER. -REFERENCES 1 LEON J.?BERCOV1TZ, 'Exandir zer. 7 15 MURRAY IILLMA N, Primary Examiner.

I A KOLASCH, J. L AssistantExaminers. 

1. A BLEND OF (A) A MEMBER OF THE GROUP CONSISTING OF POLYVIYL CHLORIDE AND COPOLYMERS OF VINYL CHLORIDE WITH A MINOR AMOUNT OF ANOTHER MONOMER COPOLYMERIZABE THEREWITH AND (B) A MEMBER OF THE GROUP CONSISTING OF HOMOPOLYMERS OF AN ALKYL B-VINYLPROPIONATE IN WHICH THE ALKYL GROUP CONTAINS ONE TO FOUR CARBON ATOMS AND COPOLYMERS THEREOF WITH ANOTHER MONOMER COPOLYMERIZABLE THEREWITH. 